Dynamic fabric phase sorptive extraction for a group of pharmaceuticals and personal care products from environmental waters

Exploring the potentialities of a biodegradable polymeric film in sample preparation: An optimized "white" protocol to extract and quantify emerging contaminants in water

BACKGROUND

The introduction of white analytical chemistry encourages the development of methods characterized by a balance among greenness, productivity/feasibility and analytical performances. In the environmental analysis of emerging contaminants (ECs), for which high sensitivity and specificity are mandatory, the use of green and sustainable sample preparation needs to be coupled to a reliable analytical determination. Herein, an extraction method based on the use of a biodegradable polymeric film (Mater-Bi) and coupled to LC-MS/MS analysis was developed for the sensitive determination of ECs in wastewater.

RESULTS

The interaction among a range of ECs and the Mater-Bi film (a commercially available patented blend of polybutylene-terephthalate, starch and fatty acids) was investigated by two sequential experimental designs, to simultaneously study several factors and optimize extraction efficiency. The final method, resembling a fabric phase sorptive extraction, involved pH and ionic strength modification of the sample, 1h extraction and desorption in ethanol. Satisfactory recoveries from real wastewater were obtained for sixteen analytes (56-116 %), as well as excellent precision (inter-day relative standard deviations below 10 % for most compounds). Matrix effect was in the range 88-116 % at the lower pre-concentration factor, but also acceptable in most cases at the higher pre-concentration factor. LODs in matrix, from 0.004 to 0.159 μg L-1, were lower than or comparable to those from recent studies employing green extraction procedures. The method demonstrated its applicability to samples from wastewater treatment plants, allowing quantification of pharmaceuticals and UV filters at the μg L-1 and ng L-1 levels, respectively.

SIGNIFICANCE

For the first time, the synthetic biopolymer Mater-Bi, so far unexplored for the use in analytical chemistry, was exploited for a green, simple and extremely cheap extraction protocol. The optimized method is suitable for several ECs, guaranteeing very good accuracy, precision and specificity, also thanks to the LC-MS/MS analysis. The evaluation by green and white analytical chemistry metrics highlighted its superiority to conventional extraction methods.

Stirred discs from polycaprolactone nanofibers highly doped with graphene for straightforward preconcentration of pollutants in environmental waters

A novel sorbent for solid phase extraction (SPE) based on hybrid nanofibrous polycaprolactone containing graphene nanoparticles has been prepared. The preparation of hybrid polymer nanofibers with a very high 1:1 polymer/graphene ratio was achieved for the first time using alternating current electrospinning. The final appearance of these nanofibers was a thick porous layer that was cut into the shape of easy-to-handle extraction discs. Based on the preliminary study in which the graphene content varied, 30% graphene-doped nanofibers (w/w) exhibited the highest recoveries and enabled a significant increase in the retention of analytes, 2-25 times in comparison to PCL. The incorporation of graphene resulted in a higher surface area of 12 g/m2 compared to 2 g/m2 determined for the native polycaprolactone (PCL) nanofibers. This unique material was applied for a simple stirred disc sorptive extraction and preconcentration of trace levels of emerging organic environmental contaminants, bisphenols A, AF, AP, C, S, Z, 3-chlorophenol, and pesticides fenoxycarb, deltamethrin, and kadethrin from surface waters prior to HPLC-DAD determination. This was accomplished by stirring the unsupported nanofiber disc in a large-volume sample with RSD of five extractions of 3-15%. Recoveries yielded 87-120%, except 52% for bisphenol S due to its high polarity. Optimization of the extraction procedure included conditioning, sample volume, extraction time, and elution solvent. Our novel desorption procedure carried out in a vial used for the direct injection into the HPLC system significantly reduced sample handling and minimized potential human error.

Non-steroidal anti-inflammatory drugs (NSAIDs) in the environment: Updates on pretreatment and determination methods

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used in human and animal health care to reduce persistent inflammation, pain and fever because of their anti-inflammatory, analgesic and antipyretic effects. However, the improper discharge and disposal make it becomes a major contaminant in the environment, which poses a big threat to the ecosystem. For this reason, accurate, sensitive, effective, green, and economic techniques are urgently required and have been rapidly developed in recent years. This review summarizes the advancement of sample preparation technologies for NSAIDs involving solid-phase extraction, solid-phase microextraction, liquid-phase microextraction, QuEChERS, and matrix solid-phase dispersion. Meanwhile, we overview and compare analytical technologies for NSAIDs, including liquid chromatography-based methods, gas chromatography-based methods, capillary electrophoresis, and sensors, particularly the development of liquid chromatography-based methods. Furthermore, we focus on their progress and conduct a comparison between their advantages and disadvantages.

Potential of hydrophobic paper-based sorptive phase prepared by in-situ thermal imidization for the extraction of methadone from oral fluid samples

Paper-based sorptive phases (PSPs) are functional planar materials with a demonstrated potential in analytical sample preparation. This article describes the synthesis of a polyimide coated paper by an in-situ imidization at a high temperature. Polyimides (PI) are synthesized in two subsequent steps where a hydrophilic polymer, in this case, poly(amic acid) (PAA), is formed as an intermediate product. PAA is finally transformed into hydrophobic PI by thermal curing at 180 °C. The synthesis of PI-paper takes advantage of this two-step procedure. In the first stage, a segment of filter paper is immersed into an aqueous PAA solution. After the solvent evaporation, the paper is heated at 180 °C for 1 h inducing the formation of the hydrophobic PI over the cellulose fibers. Infrared spectroscopy has been used to characterize the synthesized materials by defining a coverage factor F. The hydrophobicity of the materials has been studied using an aqueous methylene blue solution as a marker. To fully demonstrate the usefulness of the material in the sample preparation field, the extraction of methadone from oral fluid (OF) samples has been considered as a model analytical problem. The main variables affecting the synthesis (PAA concentration on the precursor solution and number of dips) and the extraction (elution and extraction times) have been fully evaluated. Working under the optimum conditions, a limit of quantification of 9 µg/L, intraday and interday precision better than 14.6%, and accuracy in the range of 87-108% were obtained.

Determination of phenolic compounds in human saliva after oral administration of red wine by high performance liquid chromatography

Red wine is a relevant source of bioactive compounds, which contribute to its antioxidant activity and other beneficial advantages for human health. However, the bioavailability of phenols in humans is not well understood, and the inter-individual variability in the production of phenolic compounds has not been comprehensively assessed to date. The present work describes a new method for the extraction and analysis of phenolic compounds including gallic acid (Gal), vanillic acid (Van), caffeic acid (Caf), syringic acid (Sir); (-)-epicatechin (Epi); p-coumaric acid (Cum) and resveratrol (Rsv) in human saliva samples. The target analytes were extracted using Fabric Phase Sorptive Extraction (FPSE), and subsequently analysed by high-performance liquid chromatography (HPLC) coupled with photodiode array detector (PDA). Chromatographic separation was achieved using a Symmetry C18 RP column in gradient elution mode, with methanol and phosphate buffer as the mobile phases. The linearity (intercept, slope, and determination coefficient) was evaluated in the range from 1 to 50 µg/mL. The limit of quantification (LOQ) was 1 µg/mL (LLOQ ≥0.8 µg/mL), whereas limit of detection was 0.25 µg/mL. The intra and inter-day RSD% and BIAS% values were less than± 15%. The analytical performances were further tested on human saliva collected from healthy volunteers after administering red wine. To the best of our knowledge, this is the first FPSE procedure for the analysis of phenols in saliva, using a non-invasive and easy to perform sample collection protocol. The proposed fast and inexpensive approach can be deployed as a reliable tool to study other biological matrices to proliferate understanding of these compounds distribution in human body.

Green bioanalytical sample preparation: fabric phase sorptive extraction

Fabric phase sorptive extraction (FPSE) is a recently introduced sample preparation technique that has attracted substantial interest of the scientific community dealing with bioanalysis. This technique is based on a permeable and flexible substrate made of fabric, coated with a sol-gel organic-inorganic sorbent. Among the benefits of FPSE are its tunable selectivity, adjustable porosity, minimized sample preparation workflow, substantially reduced organic solvent consumption, rapid extraction kinetics and superior extraction efficiency, many of which are well-known criteria for Green Analytical Chemistry. As such, FPSE has established itself as a leading green sample preparation technology of 21st century. In this review, we discuss the principal steps for the development of an FPSE method, the main method optimization strategies, as well as the applications of FPSE in bioanalysis for the extraction of a wide range of analytes (e.g., estrogens, benzodiazepines, androgens and progestogens, penicillins, anti-inflammatory drugs, parabens etc.).

Determination of Intact Parabens in the Human Plasma of Cancer and Non-Cancer Patients Using a Validated Fabric Phase Sorptive Extraction Reversed-Phase Liquid Chromatography Method with UV Detection

Parabens have been widely employed as preservatives since the 1920s for extending the shelf life of foodstuffs, medicines, and daily care products. Given the fact that there are some legitimate concerns related to their potential multiple endocrine-disrupting properties, the development of novel bioanalytical methods for their biomonitoring is crucial. In this study, a fabric phase sorptive extraction reversed-phase liquid chromatography method coupled with UV detection (FPSE-HPLC-UV) was developed and validated for the quantitation of seven parabens in human plasma samples. Chromatographic separation of the seven parabens and p-hydroxybenzoic acid was achieved on a semi-micro Spherisorb ODS1 analytical column under isocratic elution using a mobile phase containing 0.1% (v/v) formic acid and 66% 49 mM ammonium formate aqueous solution in acetonitrile at flow rate 0.25 mL min⁻¹ with a 24-min run time for each sample. The method was linear at a concentration range of 20 to 500 ng mL⁻¹ for the seven parabens under study in human plasma samples. The efficiency of the method was proven with the analysis of 20 human plasma samples collected from women subjected to breast cancer surgery and to reconstructive and aesthetic breast surgery. The highest quantitation rates in human plasma samples from cancerous cases were found for methylparaben and isobutylparaben with average plasma concentrations at 77 and 112.5 ng mL⁻¹. The high concentration levels detected agree with previous findings for some of the parabens and emphasize the need for further epidemiological research on the possible health effects of the use of these compounds.

Fabric Phase Sorptive Extraction: A Paradigm Shift Approach in Analytical and Bioanalytical Sample Preparation

Fabric phase sorptive extraction (FPSE) is an evolutionary sample preparation approach which was introduced in 2014, meeting all green analytical chemistry (GAC) requirements by implementing a natural or synthetic permeable and flexible fabric substrate to host a chemically coated sol-gel organic-inorganic hybrid sorbent in the form of an ultra-thin coating. This construction results in a versatile, fast, and sensitive micro-extraction device. The user-friendly FPSE membrane allows direct extraction of analytes with no sample modification, thus eliminating/minimizing the sample pre-treatment steps, which are not only time consuming, but are also considered the primary source of major analyte loss. Sol-gel sorbent-coated FPSE membranes possess high chemical, solvent, and thermal stability due to the strong covalent bonding between the fabric substrate and the sol-gel sorbent coating. Subsequent to the extraction on FPSE membrane, a wide range of organic solvents can be used in a small volume to exhaustively back-extract the analytes after FPSE process, leading to a high preconcentration factor. In most cases, no solvent evaporation and sample reconstitution are necessary. In addition to the extensive simplification of the sample preparation workflow, FPSE has also innovatively combined the extraction principle of two major, yet competing sample preparation techniques: solid phase extraction (SPE) with its characteristic exhaustive extraction, and solid phase microextraction (SPME) with its characteristic equilibrium driven extraction mechanism. Furthermore, FPSE has offered the most comprehensive cache of sorbent chemistry by successfully combining almost all of the sorbents traditionally used exclusively in either SPE or in SPME. FPSE is the first sample preparation technique to exploit the substrate surface chemistry that complements the overall selectivity and the extraction efficiency of the device. As such, FPSE indeed represents a paradigm shift approach in analytical/bioanalytical sample preparation. Furthermore, an FPSE membrane can be used as an SPME fiber or as an SPE disk for sample preparation, owing to its special geometric advantage. So far, FPSE has overwhelmingly attracted the interest of the separation scientist community, and many analytical scientists have been developing new methodologies by implementing this cutting-edge technique for the extraction and determination of many analytes at their trace and ultra-trace level concentrations in environmental samples as well as in food, pharmaceutical, and biological samples. FPSE offers a total sample preparation solution by providing neutral, cation exchanger, anion exchanger, mixed mode cation exchanger, mixed mode anion exchanger, zwitterionic, and mixed mode zwitterionic sorbents to deal with any analyte regardless of its polarity, ionic state, or the sample matrix where it resides. Herein we present the theoretical background, synthesis, mechanisms of extraction and desorption, the types of sorbents, and the main applications of FPSE so far according to different sample categories, and to briefly show the progress, advantages, and the main principles of the proposed technique.

Application of sorptive micro-extraction techniques for the pre-concentration of antibiotic drug residues from food samples - a review

Antibiotic residues have become a major concern worldwide as food contaminants due to the risk that they may pose to human health. The presence of these residues in food is due to improper veterinary practices. Consequently, rapid and cost-effective clean-up methods prior to analysis for these residues in food matrices are increasingly becoming necessary in order to ensure food safety. Miniaturised extraction and pre-concentration techniques have been developed as alternatives to conventional extraction procedures in recent years. Furthermore, the current trends in analytical sample preparation favour extraction techniques that comply with the principles of green analytical chemistry. Solid phase micro-extraction, stir bar sorptive extraction, stir cake sorptive extraction and fabric phase sorptive extraction methods are very promising sorbent-based sorptive micro-extraction techniques, and they are compliant to the principles of green chemistry. This review critically discusses the application of these techniques in the extraction and pre-concentration of antibiotic residues from food samples in the years 2015 to 2020.

Exploring the Efficiency of UHPLC-Orbitrap MS for the Determination of 20 Pharmaceuticals and Acesulfame K in Hospital and Urban Wastewaters with the Aid of FPSE

Aside from the classical residues of persistent organic pollutants (POPs), the occurrence of emerging contaminants (ECs) in the environment has become a subject of increasing concern due to their harmful impact on the aquatic environment. Wastewater treatment plant (WWTP) effluents are major sources of environmental pollution. Therefore, data concerning their existence is required. In this study, twenty compounds representative of different drug groups considered ECs and belonging to antibiotics, antipsychotics, anti-inflammatory drugs plus acesulfame K were selected to be accurately detected and quantified with UHPLC–LTQ-Orbitrap MS in hospital and urban WWTP effluents. Chromatographic parameters (column efficiency, mobile phase, etc.), as well as mass spectrometry conditions concerning ionization mode and Orbitrap analysis (ESI options, mass resolving power, AGC target, tube lens, injection time), were evaluated. Moreover, a novel fabric phase sorptive extraction (FPSE) method based on fiber glass coated with PEG300 was employed as sample preparation process. Experimental parameters affecting extraction and desorption steps such as sample pH, extraction time, ionic strength, elution time and solvent have been optimized. The optimized methodology was validated providing excellent linearity (R2 > 0.99), and low detection and quantification limits up to 3.1 and 9.3 ng/L, for carbamazepine, respectively. Relative recoveries ranged from 81.1% to 114.0%, while a medium matrix effect for most of the target compounds occurred. Applying the above analytical method in effluents of WWTPs from NW Greece, nine compounds were quantified with concentrations that varied from 55.4 to 728.4 ng/L.

Investigating the Utility of Fabric Phase Sorptive Extraction and HPLC-UV-Vis/DAD to Determine Antidepressant Drugs in Environmental Aqueous Samples

Depression is considered to be one of the most prevalent mental disorders in humans. Antidepressant drugs are released in large concentrations and cause adverse effects on the environment and/or human health. Fabric Phase Sorptive Extraction (FPSE), a contemporary solid sorbent-handling technique, is a quick, sensitive, and simple analytical process. This paper describes a micro-extraction FPSE procedure coupled with High-Performance Liquid-Chromatography–Photodiode Array Detection (FPSE-HPLC–DAD) for the simultaneous extraction and analysis of five antidepressants, namely citalopram, clozapine, mirtazapine, bupropion and sertraline. Three fabric media (Whatman Cellulose filter, Whatman Microfiber Glass filter and Polylactic acid disks) and two different sol–gel sorbents (polyethylene glycol (PEG 300), alongside poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEG-PPG-PEG 5.800)) were tested. The best FPSE device was observed to be the microfiber glass filter coated with PEG 300 sol–gel sorbent. In addition, the parameters that affect the efficiency of the process (FPSE media and sorbents, sample pH, extraction time, elution time, etc.) were optimized. The proposed methodology displays a linear range with absolute recovery values higher than 60%, RSD% of less than 13% and LOQs in the range between 1.9–10.7 μg·L−1. Finally, the method was applied in hospital and urban effluents and lake water samples, but none of the analytes were detected.

Fabric phase sorptive extraction for the determination of 17 multiclass fungicides in environmental water by gas chromatography-tandem mass spectrometry

A rapid environmental pollution screening and monitoring workflow based on fabric phase sorptive extraction-gas chromatography-tandem mass spectrometry (FPSE-GC-MS/MS) is proposed for the first time for the analysis of 17 widespread used fungicides (metalaxyl, cyprodinil, tolylfluanid, procymidone, folpet, fludioxonil, myclobutanil, kresoxim methyl, iprovalicarb, benalaxyl, trifloxystrobin, fenhexamid, tebuconazole, iprodione, pyraclostrobin, azoxystrobin and dimethomorph) in environmental waters. The most critical parameters affecting FPSE, such as sample volume, matrix pH, desorption solvent and time, and ionic strength were optimized by statistical design of experiment to obtain the highest extraction efficiency. Under the optimized conditions, the proposed FPSE-GC-MS/MS method was validated in terms of linearity, repeatability, reproducibility, accuracy and precision. To assess matrix effects, recovery studies were performed employing different water matrices including ultrapure, fountain, river, spring, and tap water at 4 different concentration levels (0.1, 0.5, 1 and 5 µg/L). Recoveries were quantitative with values ranging between 70-115%, and relative standard deviation values lower than 14%. Limits of quantification were at the low ng/L for all the target fungicides. Finally, the validated FPSE-GC-MS/MS method was applied to real water samples, revealing the presence of 11 out of the 17 target fungicides.

A Polydimethylsiloxane Rod Extraction-Based Method for the Determination of Pharmaceuticals and Triclosan by Liquid Chromatography in Water Samples

A new analytical method for the determination of naproxen, ketoprofen, diclofenac, carbamazepine, and triclosan (TCS) in water samples by liquid chromatography is developed and validated. The method is based on the extraction of the analytes by a polydimethylsiloxane (PDMS) rod. The different parameters affecting extraction, such as the addition of salt, pH, initial volume, extraction and elution times and elution solvent, as well as the application of sonication, are studied. The results showed that the detection limits are all in the 0.1-0.3 µg L^-1 range except for carbamazepine (6 µg L^-1) with relative standard deviations in the range of 0.4%-9.7%. The method developed, which was validated by analysing spiked surface water samples at 10, 25 and 75 µg L^-1 gave recoveries of between 84.8% and 111.2%. In the case of carbamazepine, a recovery of 99.1% was obtained at 75 µg L^-1. The main advantage of the developed method is that allows high performance liquid chromatography-diode array detection, which is widely available in non-specialised laboratories, to be applied for pharmaceuticals and TCS determination in surface waters after performing a preconcentration/clean-up step with PDMS rods as it has been shown by analysing real water samples.

Development of an analytical methodology based on fabric phase sorptive extraction followed by gas chromatography-tandem mass spectrometry to determine UV filters in environmental and recreational waters

A novel method based on fabric phase sorptive extraction (FPSE) followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) has been validated for the simultaneous determination of 11 UV filters (ethylhexyl salicylate, benzyl salicylate, homosalate, benzophenone-3, isoamylmethoxycinnamate, 4-methylbenzylidenecamphor, methyl anthranilate, etocrylene, 2-ethylhexylmethoxycinnamate, 2-ethylhexyl p-dimethylaminobenzoate, and octocrylene), in natural and recreational waters. Major experimental parameters affecting FPSE procedure have been optimized to obtain the highest extraction efficiency. Different types and sizes of sol-gel coated FPSE media, sample volume, extraction time, and type and volume of desorption solvent were evaluated. The optimal conditions involved the use of a (2.0 × 2.5) cm² FPSE device with PDMS based coating for the extraction of 20 mL of water for 20 min. The quantitative desorption of the target compounds was performed with 0.5-1 mL of ethyl acetate. The method was satisfactorily validated in terms of linearity, precision, repeatability and reproducibility. Recovery studies were performed at different concentration levels in real water matrices to show its suitability, obtaining mean values about 90% and satisfactory precision. LODs were at the low ng L^-1 in all cases. Finally, the validated FPSE-GC-MS/MS method was applied to different real samples, including environmental water (lake, river, seawater) and recreational water (swimming-pool), where 8 out of the 11 studied compounds were detected at concentrations between 0.12-123 μg L^-1. FPSE is proposed as an efficient and simple alternative to other extraction and microextraction techniques for the analysis of UV filters in waters. Since no matrix effects were observed, quantification could be carried out by conventional calibration with standard solutions, without the need to perform the complete FPSE procedure, thus allowing a higher throughput in comparison with other microextraction techniques.

Recent Applications and Newly Developed Strategies of Solid-Phase Microextraction in Contaminant Analysis: Through the Environment to Humans

The present review aims to describe the recent and most impactful applications in pollutant analysis using solid-phase microextraction (SPME) technology in environmental, food, and bio-clinical analysis. The covered papers were published in the last 5 years (2014–2019) thus providing the reader with information about the current state-of-the-art and the future potential directions of the research in pollutant monitoring using SPME. To this end, we revised the studies focused on the investigation of persistent organic pollutants (POPs), pesticides, and emerging pollutants (EPs) including personal care products (PPCPs), in different environmental, food, and bio-clinical matrices. We especially emphasized the role that SPME is having in contaminant surveys following the path that goes from the environment to humans passing through the food web. Besides, this review covers the last technological developments encompassing the use of novel extraction coatings (e.g., metal-organic frameworks, covalent organic frameworks, PDMS-overcoated fiber), geometries (e.g., Arrow-SPME, multiple monolithic fiber-SPME), approaches (e.g., vacuum and cold fiber SPME), and on-site devices. The applications of SPME hyphenated with ambient mass spectrometry have also been described.

Innovative Configurations of Sample Preparation Techniques Applied in Bioanalytical Chemistry: A Review

Background:

Recently, in all fields of analytical chemistry, increased attention has been paid to extraction procedures and instrumental methods, which are easily scalable and are able to automate in order to improve the “high-throughput” capability.

Introduction:

The main goal of these applications relates to an improvement of the precision in the quantitative analysis, reduction of different sources of errors, decrease the analysis time and, in general, improve the analytical performances. Often these points can be in contrast to each other, not allowing to achieve the expected result but forcing a compromise between the objectives of the method and the analytical performance.

Methods:

In this review, following the evolution of the (micro)extraction procedures and instrument configurations, the recent procedures used in bioanalytical chemistry are critically evaluated. The aim of this paper is providing an overview of the approaches available in order to perform on-line coupling of various extraction techniques with chromatographic methods for the analysis of different compounds in various samples. Furthermore, a comparison between off-line and on-line systems, advantages of on-line systems applied on major extractive techniques and future perspectives are described.

Result:

The extraction methods suitable for on-line coupling covered in this review are: liquid-liquid extraction (LLE), solid phase extraction (SPE), solid phase microextraction (SPME), dispersive liquid- liquid microextraction (DLLME), microextraction by packed sorbent (MEPS), supercritical fluid extraction (SFE) and fabric phase sorptive extraction (FPSE).

Conclusion:

An overview of the micro-extraction techniques mentioned above was provided, making a comparison between them and focusing attention on future perspectives.

Fabric Phase Sorptive Extraction-A Metabolomic Preprocessing Approach for Ionizing Radiation Exposure Assessment

The modern application of mass spectrometry-based metabolomics to the field of radiation assessment and biodosimetry has allowed for the development of prompt biomarker screenings for radiation exposure. Our previous work on radiation assessment, in easily accessible biofluids (such as urine, blood, saliva), has revealed unique metabolic perturbations in response to radiation quality, dose, and dose rate. Nevertheless, the employment of swift injury assessment in the case of a radiological disaster still remains a challenge as current sample processing can be time consuming and cause sample degradation. To address these concerns, we report a metabolomics workflow using a mass spectrometry-compatible fabric phase sorptive extraction (FPSE) technique. FPSE employs a matrix coated with sol-gel poly(caprolactone-b-dimethylsiloxane-b-caprolactone) that binds both polar and nonpolar metabolites in whole blood, eliminating serum processing steps. We confirm that the FPSE preparation technique combined with liquid chromatography-mass spectrometry can distinguish radiation exposure markers such as taurine, carnitine, arachidonic acid, α-linolenic acid, and oleic acid found 24 h after 8 Gy irradiation. We also note the effect of different membrane fibers on both metabolite extraction efficiency and the temporal stabilization of metabolites in whole blood at room temperature. These findings suggest that the FPSE approach could work in future technology to triage irradiated individuals accurately, via biomarker screening, by providing a novel method to stabilize biofluids between collection and sample analysis.

Rapid Monitoring of Organochlorine Pesticide Residues in Various Fruit Juices and Water Samples Using Fabric Phase Sorptive Extraction and Gas Chromatography-Mass Spectrometry

Fabric phase sorptive extraction, an innovative integration of solid phase extraction and solid phase microextraction principles, has been combined with gas chromatography-mass spectrometry for the rapid extraction and determination of nineteen organochlorine pesticides in various fruit juices and water samples. FPSE consolidates the advanced features of sol-gel derived extraction sorbents with the rich surface chemistry of cellulose fabric substrate, which could extract the target analytes directly from the complex sample matrices, substantially simplifying the sample preparation operation. Important FPSE parameters, including sorbent chemistry, extraction time, stirring speed, type and volume of back-extraction solvent, and back-extraction time have been optimized. Calibration curves were obtained in a concentration range of 0.1–500 ng/mL. Under optimum conditions, limits of detection were obtained in a range of 0.007–0.032 ng/mL with satisfactory precision (RSD < 6%). The relative recoveries obtained by spiking organochlorine pesticides in water and selected juice samples were in the range of 91.56–99.83%. The sorbent sol-gel poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) was applied for the extraction and preconcentration of organochlorine pesticides in aqueous and fruit juice samples prior to analysis with gas chromatography-mass spectrometry. The results demonstrated that the present method is simple, rapid, and precise for the determination of organochlorine pesticides in aqueous samples.

Fabric Phase Sorptive Extraction: Current State of the Art and Future Perspectives

Fabric phase sorptive extraction (FPSE) is a novel and green sample preparation technique introduced in 2014. FPSE utilizes a natural or synthetic permeable and flexible fabric substrate chemically coated with a sol-gel organic-inorganic hybrid sorbent in the form of ultra-thin coating, which leads to a fast and sensitive micro-extraction device. The flexible FPSE requires no modification of samples and allows direct extraction of analytes. Sol-gel sorbent-coated FPSE media possesses high chemical, solvent, and thermal stability due to the strong covalent bonding between the substrate and the sol-gel sorbent. Therefore, any elution solvent can be used in a small volume, which achieves a high pre-concentration factor without requiring any solvent evaporation and sample reconstitution step. Taking into consideration the complexity of the samples and the need of further minimization and automation, some new, alternative modes of the FPSE have also been developed. Therefore, FPSE has attracted the interest of the scientific community that deals with sample pre-treatment and has been successfully applied for the extraction and determination of many analytes in environmental samples as well as in food and biological samples. The objective of the current review is to present and classify the applications of FPSE according to different sample categories and to briefly show the progress, advantages, and the main principles of the proposed technique.

Fabric Phase Sorptive Extraction Explained

The theory and working principle of fabric phase sorptive extraction (FPSE) is presented. FPSE innovatively integrates the benefits of sol–gel coating technology and the rich surface chemistry of cellulose/polyester/fiberglass fabrics, resulting in a microextraction device with very high sorbent loading in the form of an ultra-thin coating. This porous sorbent coating and the permeable substrate synergistically facilitate fast extraction equilibrium. The flexibility of the FPSE device allows its direct insertion into original, unmodified samples of different origin. Strong chemical bonding between the sol–gel sorbent and the fabric substrate permits the exposure of FPSE devices to any organic solvent for analyte back-extraction/elution. As a representative sorbent, sol–gel poly(ethylene glycol) coating was generated on cellulose substrates. Five (cm2) segments of these coated fabrics were used as the FPSE devices for sample preparation using direct immersion mode. An important class of environmental pollutants—substituted phenols—was used as model compounds to evaluate the extraction performance of FPSE. The high primary contact surface area (PCSA) of the FPSE device and porous structure of the sol–gel coatings resulted in very high sample capacities and incredible extraction sensitivities in a relatively short period of time. Different extraction parameters were evaluated and optimized. The new extraction devices demonstrated part per trillion level detection limits for substitute phenols, a wide range of detection linearity, and good performance reproducibility.

Fabric Sol–gel Phase Sorptive Extraction Technique: A Review

Since the introduction in 2014 of fabric phase sorptive extraction (FPSE) as a sample preparation technique, it has attracted the attention of many scientists working in the field of separation science. This novel sorbent extraction technique has successfully utilized the benefits of sol–gel derived hybrid sorbents and a plethora of fabric substrates, resulting in a highly efficient, sensitive and green sample pretreatment methodology. The proposed procedure is an easy and efficient pathway to extract target analytes from different matrices providing inherent advantages such as high sample loading capacity and short pretreatment time. The present review mainly focuses on the background and sol–gel chemistry for the preparation of new fabric sorbents as well as on the applications of FPSE for extracting target analytes, from the time that it was first introduced. New modes of FPSE including stir FPSE, stir-bar FPSE, dynamic FPSE, and automated on-line FPSE are also highlighted and commented upon in detail. FPSE has been effectively applied for the determination of various organic and inorganic analytes in different types of environmental and biological samples in high throughput analytical, environmental, and toxicological laboratories.

An automated flow injection system for metal determination by flame atomic absorption spectrometry involving on-line fabric disk sorptive extraction technique

A novel flow injection-fabric disk sorptive extraction (FI-FDSE) system was developed for automated determination of trace metals. The platform was based on a minicolumn packed with sol-gel coated fabric media in the form of disks, incorporated into an on-line solid-phase extraction system, coupled with flame atomic absorption spectrometry (FAAS). This configuration provides minor backpressure, resulting in high loading flow rates and shorter analytical cycles. The potentials of this technique were demonstrated for trace lead and cadmium determination in environmental water samples. The applicability of different sol-gel coated FPSE media was investigated. The on-line formed complex of metal with ammonium pyrrolidine dithiocarbamate (APDC) was retained onto the fabric surface and methyl isobutyl ketone (MIBK) was used to elute the analytes prior to atomization. For 90s preconcentration time, enrichment factors of 140 and 38 and detection limits (3σ) of 1.8 and 0.4μgL(-1) were achieved for lead and cadmium determination, respectively, with a sampling frequency of 30h(-1). The accuracy of the proposed method was estimated by analyzing standard reference materials and spiked water samples.